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Fretting fatigue is a limiting factor in blade attachment design for turbomachinery. Shot peening is known to be a strength increasing measure against fatigue. It is applied not only to free surfaces of components under fatigue but also to contacting surfaces subject to fretting fatigue. The present work examines the effect of shot peening on fretting fatigue resistance in fixtures of rotor blades. The chosen integral approach allows the consideration of shot peening and subsequent fretting loading in one simulation. Thus, the residual stresses and material strengthening as well as the surface waviness due to the shot peening process are included in the fretting fatigue simulation. To achieve reasonable computation times a two-dimensioinal model, calibrated to a three-dimensional unit cell model, is employed. A comparative study on fatigue endurance limits is presented for the cases with and without shot peening. With view to the different failure mechanisms met in these two cases, an initiation evaluation is carried out with the Sines criterion for the unpeened condition; a fracture mechanics approach is shown to be necessary for the evaluation of the shot peened condition. [ABSTRACT FROM AUTHOR]

Einleitung: Die Erfassung von negativen Effekten (nE) von Psychotherapie (PT) ist wichtig, um Schwachstellen von PT zu identifizieren und die Behandlungsqualität zu verbessern. Studienziel ist, zu untersuchen, welche nE Patienten nach einer tagesklinischen Behandlung für Borderline-Persönlichkeitsstörungen (BPS) mit einem Dialektisch-Behavioralen Therapieschwerpunkt (DBT) beschreiben, welche Einflussfaktoren vorliegen und wie die Klagen inhaltlich zu verstehen sind. Material und Methoden: Katamnestisch wurden BPS-Patienten 22,6 Monate nach Therapieende befragt, an welche nE sie sich mit Bezug zu einer zwölfwöchigen ta-gesklinischen Behandlung erinnern. Messinstrumente wa-ren BDI, BSL-95 und INEP. Ergebnisse: 35 Frauen und 6 Männer antworteten (50% von 82). Im Mittel wurden 11,2 nE benannt, die subjektiv auf die DBT-Behandlung zurückgeführt wurden. 97,6% berichten von Verschlechterung ihres Befindens, 87,8% erinnern sich an Probleme in der therapeutischen Beziehung, 43,9% klagten über Verschlechterungen in der Beziehung, 70,7% über finanzielle Probleme in Folge der tagesklinischen Behandlung und 29,3% über Stigmatisierungserleben. Die Zahl der nE korrelierte mit höherem Alter zum Therapiestart (p < 0,01) sowie höherer Symptomlast anhand der BSL-95 (p < 0,01) bzw. BDI (p < 0,01) zum Befragungszeitpunkt. Diskussion: Es konnte gezeigt werden, dass Patienten bei Vorlage des INEP über eine erheb-liche Rate an Negativerfahrungen im Rahmen der tages-klinischen Behandlung klagen. Der lange Rückerinne-rungszeitraum von 3 bis 51 Monaten und die Korrelation mit der aktuellen Symptomatik stellen die Validität der Antwort in Frage. Ergebnisse von Selbstratinginstrumenten zur Nebenwirkungserfassung bedürfen einer sehr sorgfältigen Interpretation. [ABSTRACT FROM AUTHOR]

The "Faro a Colón," or "Columbus Lighthouse," is perhaps the largest memorial to Christopher Columbus in the world. Inaugurated in 1992 as a celebration of the five-hundredth anniversary of Columbus's first arrival in the Americas, it is visible throughout much of Santo Domingo, Dominican Republic. This article argues that the typical presentation of the monument is badly misaligned with the historical record, but that a historically and historiographically informed interpretation can lead to a truer understanding of the violence and greed of colonization. Contrary to what its designers wanted to show about Columbus, and in some ways in spite of itself, the Columbus Lighthouse conveys with unusual clarity the problems of memorializing one of the most (in)famous figures in world history. [ABSTRACT FROM AUTHOR]

Teaching ecology effectively and experientially has become more challenging for at least two reasons today. Most experiences of our students are urban, and we now face the near immediate and continuing need to deliver courses (either partially or wholly) online because of COVID‐19. Therefore, providing a learning experience that connects students to their environment within an ecological framework remains crucial and perhaps therapeutic to mental health. Here, we describe how prior to the pandemic we adapted our field‐based laboratories to include data collection, analysis, and interpretation, along with the development of a citizen‐science approach for online delivery. This design is simple to implement, does not require extensive work, and maintains the veracity of original learning outcomes. Collaboration online following field data collection in ecology courses within the context of cities offers further options to adapt to student experience levels, resource availability, and accessibility, as well as bringing instructors and students together to build an open well‐curated data set that can be used in ecology courses where no laboratories are available. Finally, it promotes an open collaboration among ecology instructors that can drive lasting conversations about ecology curriculum. [ABSTRACT FROM AUTHOR]

• A hybrid method to estimate the radiated noise from sparsely-instrumented vibrating casing structures is demonstrated. In a complex structural system, such as a gearbox or a motor, with partially or completely unknown set of excitation forces, the exact prediction of the vibrations of a casing encapsulating the complex system, is not possible, especially at high frequencies. For the spatial recording of the complete vibration field on the casing, it would be necessary to scan the casing surface using several vibration sensors, especially at higher frequencies. Such a high-resolution rate of sensors or recording points on the casing surface is rarely achievable in industrial tests. Moreover, usage of several optical scanning devices to scan the vibration field from every possible direction is very expensive, cumbersome and mostly ineffective. Therefore, a novel technique is developed here, which enables the calculation of the participation factors of the casing eigenmodes using a reduced number of vibration sensors on the casing, with the aim to estimate the radiated noise levels generated by the vibrating casing. This technique is based on a Compressed Sensing approach which solves an under-determined system of equations. The calculated participation factors of the eigenmodes are then used as inputs into a Finite Element Method (FEM) to calculate the radiated noise levels. The noise predictions are then compared to the measurements to achieve enough confidence level in this method for its industrial usage. [ABSTRACT FROM AUTHOR]

Einleitung: Die dialektisch-behaviorale Therapie (DBT) für Patienten mit Borderline-Persönlichkeitsstörung (BPS) ist evidenzbasiert. Es gibt jedoch nur eine kleine Anzahl von Studien, die die Frage einer möglichen anhaltenden Wirkung von DBT untersuchen. Über Prädiktoren dieser Nachhaltigkeit ist wenig bekannt. Methode: Am Beispiel eines zertifizierten tagesklinischen Settings wird der posttherapeutische Verlauf untersucht. Mögliche Prädiktoren einer Verschlechterung nach Therapieende sollen erkannt werden. Hierzu wurden Patienten der DBT-Tagesklinik, deren Daten schon in eine prospektive, naturalistische, offene und nicht kontrollierte Vorstudie eingingen, erneut retrospektiv befragt. Somit konnten die Scores der Borderline-Symptomliste 95 (BSL-95) und des Beck-Depressions-Inventars (BDI) zu 3 verschiedenen Zeitpunkten (Z1 = Start, Z2 = Therapieende, Z3 = Katamnesezeitpunkt) verglichen werden. Der Fragebogen zu «Nebenwirkungen stationärer Psychotherapien» (NESTAP) lieferte weitere mögliche Prädiktoren. Ergebnisse: Der Katamnesezeitraum betrug 3-51 Monate. 82 Patienten wurden angeschrieben, es antworteten 41. Anhand des BDI und der BSL-95 (Differenz Z1 zu Z3, p < 0,05) ist eine Symptombesserung in dieser Gruppe auch weit über das Therapieende feststellbar. In einem linearen Regressionsmodell mit einer Effektstärke von 1,04 (Cohen) zeigt eine Subgruppe (25%), gekennzeichnet durch hohe Werte des Prädiktors «Dysphorie» im BSL-95 (Z2 zu Z1) eine geringe anhaltende Wirkung der DBT (Differenz der BSL-95- und BDI-Scores zu Z2 und Z3). Schlussfolgerungen: Es konnten Hinweise für ein tagesklinisches DBT-Programm zur anhaltenden Symptombesserung bis 51 Monate nach Therapieende dargestellt werden. Für 50% der Patienten ist hierfür keine Aussage möglich. Auch gab es keine Kontrollgruppe. Die Veränderung von «Dysphorie» während der Therapiephase scheint diese therapeutische Wirkung über diesen Katamnesezeitraum zu beeinflussen. Weitere Studien sollten folgen, um die Daten zu prüfen oder andere Prädiktoren zu finden. [ABSTRACT FROM AUTHOR]

Big Data comprises a variety of diverse practices, which reach beyond established procedures of scientific social research. This article discusses three qualities of Big Data research: (1) The immediate conjunction of analysis and action. From a social science perspective this is perceived as an illegitimate shortcut. (2) Three different understandings of data and their respective objectivity. (3) The emergence of new commercial and governmental data processing collectices. The article concludes with drawing consequences for educational sciences and outlining a respective research program. [ABSTRACT FROM AUTHOR]

Biological and technical systems operate in a rich multimodal environment. Due to the diversity of incoming sensory streams a system perceives and the variety of motor capabilities a system exhibits there is no single representation and no singular unambiguous interpretation of such a complex scene. In this work we propose a novel sensory processing architecture, inspired by the distributed macro-architecture of the mammalian cortex. The underlying computation is performed by a network of computational maps, each representing a different sensory quantity. All the different sensory streams enter the system through multiple parallel channels. The system autonomously associates and combines them into a coherent representation, given incoming observations. These processes are adaptive and involve learning. The proposed framework introduces mechanisms for self-creation and learning of the functional relations between the computational maps, encoding sensorimotor streams, directly from the data. Its intrinsic scalability, parallelisation, and automatic adaptation to unforeseen sensory perturbations make our approach a promising candidate for robust multisensory fusion in robotic systems. We demonstrate this by applying our model to a 3D motion estimation on a quadrotor. [ABSTRACT FROM AUTHOR]

The present study aimed to assess (1) the amount of inpatient and day clinic DBT treatment places for patients with borderline personality disorder and (2) the relationship between supply and demand in a given study region. Survey of inpatient and day clinic facilities in the German DBT network. 42 inpatient units and day clinics responded, representing 75 % of the DBT network members contacted. These institutions offer 527 DBT treatment places and treat about 2310 patients per year. The mean waiting period prior to treatment was 14.3 weeks. 700 DBT inpatient or day clinic places exist in Germany in 2011. 3000 patients receive DBT inpatient or day clinic treatment per year. This approximates a ratio of 820 borderline patients for one existing DBT inpatient or day clinic place in Germany. The long waiting time reflects the great demand for this treatment and could be interpreted as an imbalance between supply and demand. [ABSTRACT FROM AUTHOR]

Hintergrund: Deutschlandweite, retrospektive Erfassung der stationären und tagesklinischen DBT-Versorgung von Patienten mit Borderline-Persönlichkeitsstörung (BPS) für das Jahr 2011: Anzahl der Behandlungsplätze; Patienten pro Jahr; Wartezeit; Behandlungsdauer; Subspezialisierung; Vernetzung stationärer, tagesklinischer bzw. ambulanter Therapieangebote. Methoden: Fragebogenversendung über E-Mail-Verteiler des DBT-Dachverbands. Ergebnisse: 42 Krankenhäuser und Tageskliniken gaben Rückmeldung (Rücklaufquote: 75%, 527 Therapieplätze, 2310 behandelte Patienten). Die mittlere Wartezeit betrug 14,3 Wochen. Die mittlere Behandlungsdauer betrug ≥9,6 Wochen und ≤20,3 Wochen. 52,2% der antwortenden Einrichtungen waren durch den Dachverband zertifiziert (allerdings nur 7,1% der Tageskliniken). 57,1% boten eine Subspezialisierung an, 14,3% eine separierte Diagnose- und Behandlungsphase, 92,1% sahen ein tagesklinisches Angebot als wünschenswert an, aber nur 28,6% besaßen ein solches. 38,1% boten einen Wechsel zwischen stationären, tagesklinischen oder ambulanten Therapieoptionen an (Therapeutenwechsel in 61% der Fälle). In Bezug auf die Übernahme höherer Behandlungskosten, die durch die DBT entstanden waren, hatten nur 4,8% der Einrichtungen spezielle Vertragsvereinbarungen mit Krankenkassen. Schlussfolgerungen: Grundlage dieses Beitrags ist eine erste systematisierte Umfrage im deutschsprachigen Raum. Im Jahr 2011 gab es in Deutschland hochgerechnet 700 vollstationäre und tagesklinische DBT-Behandlungsplätze für etwa 3000 Patienten mit BPS. Das Verhältnis von einem DBT-Platz zu 191 Patienten pro Jahr sowie die lange Wartezeit waren Indikatoren für ein zu geringes Angebot (teil)stationärer DBT, das die Nachfrage bei Weitem nicht decken konnte; gleichzeitig bestand eine ambulante Versorgungslücke. [ABSTRACT FROM AUTHOR]

The article discusses the scope of shared assumptions presented by positions in the fields of computer science education and critical digital literacy concerning the skills required for a participation in a digital world. Based on respective notions of design, a notion of collaborative design literacy is developped, understood as a the ability to participate with others in multi-perspective processes of technological development to be able to design a desirable future. [ABSTRACT FROM AUTHOR]

The color of textile fibers is typically imparted by submersion in a high-temperature dye bath. However, the treatment of the effluent is challenging and the textile industry is therefore a major source of water pollution. Current fashion trends favor biobased polymers such as polylactic acid (PLA) but exhaust dyeing at high temperatures causes hydrolytic degradation, reducing the crystallinity and tenacity of the yarn. To preserve the mechanical properties of PLA-based textiles, an alternative to exhaust dyeing called dope dyeing can be used, wherein colorants are incorporated into the polymer matrix during melt spinning. We evaluated this process by dope dyeing PLA with several colorants, then testing the thermal, physical, and mechanical properties of the yarn and the physical properties of circular-knitted fabrics. Although the colorants affected the crystallization behavior at lower cooling rates, during the melt-spinning process, the drawing speed had a greater effect on the crystallinity and mechanical properties of the dyed yarn. Scanning electron microscopy revealed that the colorants were well dispersed in the PLA matrix. We found that the colorants did not affect the physical properties of the knitted fabric. Our results can be used to develop more environmentally beneficial dope-dyed PLA yarn with improved mechanical properties. [ABSTRACT FROM AUTHOR]

This paper presents the results of insertion loss measurements and numerical impedance eduction of three different liner samples. An overview of the test rig and methodology is given, and preprocessed results in terms of reflection and transmission coefficients as well as the energy dissipation are discussed. These coefficients are calculated for discrete frequencies within the investigated frequency range. Subsequently, a numerical postprocessing is performed in the time domain, and the educed impedance function for each sample and flow Mach number is presented. This postprocessing in the time domain uses an impedance model based on the extended Helmholtz resonator with five free parameters. The parameters of the model are fitted via an optimization, which determines the whole frequency response in one optimization process. The comparison of measured and numerically evaluated energy coefficients proves the reliability of the tools for impedance evaluation under flow conditions. Finally, the impedance results of the different samples are discussed, including a comparative study with Aermacchi data of the National Aerospace Laboratory (The Netherlands) flow tube and Aermacchi impedance tube experiments. [ABSTRACT FROM AUTHOR]

Abstract: Time-domain impedance boundary conditions are reviewed and similarities between the models are shown. The extended Helmholtz resonator model is used with a time-domain impedance boundary condition for impedance eduction and simulation of the noise radiation from a lined aeroengine nozzle. Model parameters obtained by impedance eduction from flow duct measurements and then used to predict the noise radiation for realistic aeroengine nozzle flow and geometry. The prediction of sound radiation from a coaxial jet nozzle at approach conditions with the educed model parameters is performed in 2D and 3D. Various features of the numerical method that enable it to be used for realistic applications are presented. This includes the suppression of flow instabilities in the linear inviscid solution and analysis of the solution to prove the global conservation of acoustic energy in each individual result. It is found that the current approach is too time consuming for optimisation, even for a 2D simulation using parallel processing. Thus, finally the potential of porting a CAA method to the graphics processing unit (GPU) is shown in one example. The GPU based computation is about 100 times faster. The results are encouraging, even though the GPU variant needs further validation. [Copyright &y& Elsevier]

The rearward propagation of tonal noise from the main fan and the engine core of modern high bypass aeroengines is one of the current demanding applications of CAA methods. One of the main features of this problem is the radiation of tones from main fan and turbine through the shear layers of core and bypass jets. This can approximately be described by a solution of the linearized perturbed Euler equations over a sheared turbulent averaged base flow field. However, these equations not only describe sound propagation, but also provide a stability analysis for the sheared base flow. Three techniques with the potential to calculate an acoustic solution and at the same time to suppress the instability are compared in this paper. The radiation of a source from a two-dimensional hot jet, chosen from a CAA workshop on benchmark problems, is considered first. Then, the techniques are adopted for the simulation of a single azimuthal mode radiating from the bypass duct of a turbofan engine, as an example for the realistic application. The first technique is based on filtering the mean flow field, over which the perturbation equations are solved. A low-order filter is applied. Subsequently, an adaption of this method, which considers a filtering of the mean flow derivatives in addition, is proved to be very beneficial. The result then reflects the analytical solution of the benchmark problem very well. The second technique filters the source terms in the governing equations. In a first attempt, all mean flow derivatives are neglected to suppress the instability. A more physical motivated variant of the approach neglects only source terms in the momentum equations. However, both provide unsatisfactory predictions of the acoustic field for the benchmark. Finally, a third technique is implemented, which considers the modification of the velocity derivatives in the momentum equations, as this method has demonstrated one of the best predictions for the benchmark problem. Nevertheless, the latter technique has no 3D extension and thus fails in suppressing the instability waves in the turbofan application. [ABSTRACT FROM AUTHOR]

Abstract: A methodology for assessing the quality and analysing the sound field of a numerical solution for an aeroacoustic problem is presented using an in-duct propagation problem as example. Namely an analysis of the acoustic energy conservation provides insight about the solution quality; sources of numerical error as well as physical source of sound are located by an analysis of the acoustic intensity; a mode analysis provides information about the sound field in the duct and a visualisation of the average pathway of sound by the acoustic intensity helps the interpretation of the modal amplitude data. The problem chosen for the presentation deals with the propagation of a single acoustic mode upstream through the tapering inlet duct of a centrifugal compressor. The propagation of tone noise is a typical problem for computational aeroacoustics. The numerical approach employs high-order finite-difference discretisation schemes with structured body-fitted meshes. An overset grid approach allows to overcome the geometrical complexity of the problem. The conservation of the acoustic energy is found to be violated by less than 3% in case of a potential base flow. In this case major sources of error are found in the interpolation between overset and background mesh. In case of a non-potential flow with boundary layers at the wall, the conservation of acoustic energy cannot be claimed. Consequently, it shows an increase of the acoustic energy, for which the accelerated flow in the nozzle is identified as source. It is shown that the filtering scheme affect the solution more than the spatial discretisation, if the grid resolution is relatively high. A strong scattering of energy into higher radial modes is detected. The fifth and sixth radial mode are found to be preferred in the current example. They are excited in the nozzle with a similar level. For these high radial modes, the transport of acoustic energy takes place further away from the duct wall. This explains the relatively large drop of about 20dB for the average sound pressure level at the wall over the inlet nozzle. [Copyright &y& Elsevier]

Abstract: The entropy noise mechanism was investigated both experimentally and numerically on a generic test case. The model experiment features electrical heating to generate non-isentropic perturbations in a spatially varying average flow field. This flow field is set by the geometrical boundary conditions of an axisymmetric convergent–divergent nozzle in an otherwise straight tube. The considered flow conditions range from low subsonic to a transonic chocked base flow. The general response of the system to an abrupt heating pulse is studied experimentally and numerically. Furthermore, for two specific cases a detailed investigation of the pressure response in the outlet section is provided. Comprehensive experimental data are provided for the validation of numerical methods with respect to entropy noise. The numerical investigations use a commercial available computational fluid dynamics (CFD) method with partially and non-reflective boundary conditions for unsteady compressible simulations on one hand and a high-order CAA method with a time-domain impedance model on the other hand. It is found that the determination of reflections from the downstream and/or upstream open ends of the test configuration are necessary for the correct prediction of the experiment. The results of both methods are analyzed for the presence of acoustic sources considering the source term of an acoustic analogy and the acoustic intensity, respectively. Strong sources are found in the convergent/divergent nozzle by both methods. These sources show a much larger source strength than the direct sources due to the unsteady heat input. A saturation of the peak pressure response with a increasing Mach number in the nozzle throat above is attributed to a phase shift of the source contributions between nozzle and diffuser. The presented results enable a deep understanding of the entropy noise phenomenon especially due to the combination of experiments and two fairly different numerical approaches. However, even in spite of the simplified model case the investigated entropy noise mechanism still appears in a comprehensive complexity. Therefore, and because of the increasing relevance as an aero-engine noise source, further research on entropy noise, also under application of the presented reference cases, should be performed. [Copyright &y& Elsevier]

In testing packaged high-power integrated circuits, active thermal control is useful in providing die-level temperature stability. A time-varying heat load is applied to the surface of the package to compensate for the time-varying test power sequence applied to the die. An earlier study determined the proper control heat load for a single-frequency sinusoidal variation in die power subject to a finite allowed temperature variation on the die. Actual lest power sequences contain many frequencies at various phase angles, each contributing to the temperature variation of the die. In the present study, we develop a method of controlling multiple frequency test sequences subject to a finite temperature tolerance. It is shown that the total control power may be minimized assigning temperature tolerances to the highest frequencies in the test power sequence. [ABSTRACT FROM AUTHOR]

Current cultural, social, and economic trends challenge traditional concepts of learning and lifelong learning. This paper draws on the twofold nature of learning in a knowledge society and explores options for technological support. The concept of Second-Order Learning Objects is introduced as a potential means to foster generative learning. Generative learning goes beyond that what is already known and extends or transforms the socially shared knowledge including its artefacts and practices. According to the notion of individual and social learning as a process of reflective action, the role of strategies and media for reflection and inquiry is stressed. This paper outlines the use of schematically represented strategies for learning and reflection and sketches important features of a pursuant modelling approach. [ABSTRACT FROM AUTHOR]

The present paper provides an overview of the structural design of modern steam turbine blades at Siemens power generation using the finite element code ADINA™. The different types of blades are described in detail regarding their geometry and loading. The modular building block approach of modelling is shown to be of essential importance. For the different analyses a fatigue post-processor has been implemented as well as an optimization tool. Both of these in-house codes will be briefly presented. [Copyright &y& Elsevier]

Recently, we demonstrated that the control of cytosolic and mitochondrial redox balance and oxidative damage is one of the primary functions of NADP+-dependent isocitrate dehydrogenase (ICDH) through to supply NADPH for antioxidant systems. NO donors such as S-nitrosothiols, diethylamine NONOate, spermine NONOate, and 3-morpholinosydnomine N-ethylcarbamide (SIN-1)/superoxide dismutase inactivated ICDH in a dose- and time-dependent manner. The inhibition of ICDH by S-nitrosothiol was partially reversed by thiol, such as dithiothreitol or 2-mercaptoethanol. Loss of enzyme activity was associated with the depletion of the cysteine-reactive 5,5′-dithiobis-(2-nitrobenzoate) and the loss of fluorescent probe N,N′-dimethyl-N(iodoacetyl)-N′-(7-nitrobenz-2-oxa-1,3-diazol-4-yl) ethyleneamine accessible thiol groups. Using electrospray ionization mass spectrometry with tryptic digestion of protein, we found that nitric oxide forms S-nitrosothiol adducts on Cys305 and Cys387. These results indicate that S-nitrosylation of cysteine residues on ICDH is a mechanism involving the inactivation of ICDH by NO. The structural alterations of modified enzyme were indicated by the changes in protease susceptibility and intrinsic tryptophan fluorescence. When U937 cells were incubated with 200 μM SNAP for 1 h, a significant decrease in both cytosolic and mitochondrial ICDH activities were observed. Furthermore, stimulation with lipopolysaccharide significantly decreased intracellular ICDH activity in RAW 264.7 cells, and this effect was blocked by NO synthase inhibitor Nω-methyl-L-arginine. This result indicates that ICDH was also inactivated by endogenous NO. The NO-mediated damage to ICDH may result in the perturbation of cellular antioxidant defense mechanisms and subsequently lead to a pro-oxidant condition. [Copyright &y& Elsevier]

Examines the social structure and residency in aggregations of male sperm whales. Complexity of the social structure of female sperm whales; Lack of long-term relationships amongst male sperm whales; Consequence of the need for care of the young sperm whales.

Studies the contrasting effects of nitric oxide and peroxynitrites on heat shock protein 70 (HSP70) expression and apoptosis in human monocytes. Results of cytofluorometric analysis of mitochondrial membrane potential; Coexistence of cells exhibiting features of apoptosis with cells exhibiting necrosis features.

Examines the effects of nitric oxide (NO) and peroxynitrite on heat shock protein-70 (HSP70) and apoptosis in human monocytes. Occurrence of dose-dependent increase in HS70 expression; Characteristics of the stress response; Induction of HSP70 expression, mitochondrial membrane depolarization and cell death by apoptosis.

Presents information on a study which investigated the extent of mitochondrial DNA (mtDNA) oxidation and fragmentation under carefully controlled conditions. Materials and methods; Results and discussion.

Presents information on a study which determined how peroxynitrite stimulates calcium2+ (Ca2+) release from isolated rat liver mitochondria. Determination of mitochondrial membrane potential; Spectrophotometric analysis of mitochondrial pyridine nucleotides; Regulation of Ca2+ release from mitochondria by nitric oxide and its congeners; Materials and methods used in study; Results of study.

Reports on the effect of gliotoxin on calcium release from intact rat liver mitochondria. Characteristics of gliotoxin; Factors affecting calcium release; Postulated mechanisms of action; Relationship with cyclosporin A; Parallelism with hydrolysis of mitochondrial pyridine nucleotides.

This article emphasizes the importance of mitochondria, the cellular ATP level, and the liberation of certain mitochondrial proteins for the execution phase of apoptosis. Destabilization of mitochondria results in release of these proteins. Oxidative stress and altered cellular Ca2+ homeostatis, considered to be mediators of apoptosis, synergistically decrease the mitochondrial membrane potential and lower the cellular ATP level. Conversely, stabilization of the mitochondrial membrane potential, e.g., by the protooncogene bcl-2, prevents cell death. An important process underlying mitochondrial destabilization is oxidant-induced mitochondrial Ca2+ release followed by re-uptake ("Ca2+ cycling"). Tumor necrosis factor-a induces oxygen radicals in mitochondria through ceramides, and the recently discovered mitochondrial nitric oxide synthase profoundly stimulates Ca2+ release from mitochondria through formation of nitrogen monoxide and peroxynitrite. [ABSTRACT FROM AUTHOR]

Purpose: Psychosocial screening for glioma patients is challenging because many patients suffer from neurocognitive deficits, which may impair assessment. This study's aim was to exploratively develop three screening questions for unmet needs to prospectively be applicable in patient–doctor consultation. Methods: Patient interviews, a survey for health-care professionals and a weighted scoring procedure were developed for this study. Six main areas were defined according to main areas of validated questionnaires (psyche, cognition, body, role functioning, social support, unmet needs). Patients and health-care professionals rated the importance of these areas and corresponding items, patients additionally stated whether the issues addressed affected them. Results: A total of 50 patients were included, and 36 health-care professionals participated in the online survey. The three areas (psyche, body and cognition) considered to be most relevant by both, health-care professionals and patients, generated three screening questions. If the patient was affected by the issue addressed with a screening question, a subordinate question from that area that our patient sample considered most important could additionally be asked. The elaborated screening questions are the following: (1) main area psyche: "Has your mood worsened?", (2) main area body: "Do physical changes put a strain on you?", and (3) main area cognition: "Has your memory capacity worsened?" Conclusion: These questions represent a basis for further research regarding their application in neuro-oncological clinical routine. [ABSTRACT FROM AUTHOR]